Cybercriminals exploit the Domain Name System (DNS) protocol to conduct a type of User Datagram Protocol (UDP) flood attack known as DNS Flood. A very high packet rate is used by cybercriminals to send out legitimate but fake DNS request packets, together with a very big collection of source IP addresses.
The target’s DNS servers start responding to each request since they appear to be legitimate requests. The volume of requests may be too much for the DNS server to handle. Large quantities of network resources are consumed by the DNS attack, wearing down the DNS infrastructure until it is shut down, cutting off the target’s internet access along with it.
DNS Flood Attack Defense
Hackers can get around the majority of anomaly detection systems by using a large number of IP addresses. Because of this, preventing DNS flood attacks can occasionally be very challenging.
However, still, there are different approaches you can take to prevent this attack:
- Keep Your Resolver Private – Ensure that no outside users can access your resolver. It is advised to limit its use to only those on your network in order to stop outside intruders from contaminating its cache.
- Use DDoS Mitigation Service – Regardless of where you maintain your DNS servers, they are vulnerable to DDoS attacks, which can interfere with business operations and render your services unavailable. It is best to use DDoS mitigation services from a reliable partner, such as Indusface, whose fully managed DDoS protection solution can help to block some of the unwanted traffic and ensure that your DNS services stay accessible, in order to prevent DNS DDoS flooding.
- Effective Patch Management Solution – It is a crucial tool for preventing DNS flood attacks. Cybercriminals enjoy profiting from software flaws and vulnerabilities. So, it’s essential to apply patches as soon as you can. Maintaining patched and current name servers helps shield them from known vulnerabilities.
- Use A Dedicated DNS Server – Due to financial limitations, small businesses frequently host their DNS server alongside their application servers. But it raises the possibility of DNS flood DDoS attacks. Running your DNS services on a dedicated server is always advised.
- Conduct a DNS Audit – Organizations frequently lose track of their previous subdomains over time. Some of them might be exploitable or employ out-of-date software. Regular DNS zone auditing will give you information on DNS-related issues and help you understand what needs to be fixed.